The invention relates to a microfilm camera with a suction plate which is provided for holding a sheet of film and which can be moved step by step across a film gate.
With cameras of this kind, in order to ensure good definition, the suction plate movable parallel to the film gate must hold the front side of the sheet of film in the plane of the bearing surface of the gate, no matter what the exposure position. Even with the narrowest manufacturing tolerances, however, this requirement cannot be satisfactorily fulfilled.
In a known microfilm camera (British Patent No. 1,051,541) the roll film movable step by step from a delivery spool to a take-up spool can be attracted alternately by the suction chamber of the rear wall during each exposure and by the suction chamber of the transport plate during each advance of the film. Owing to the attraction of the film to the rear wall during the exposure the user has to devote constant attention to any changes occurring in the thickness of the film. With a microfilm camera using sheet film, the continual detachment of the sheet from the suction plate and its re-attraction thereto involves a risk of displacement of the sheet in relation to the plate.